Refrigeration systems, particularly heat pump systems selectively heat or cool a space to be conditioned and employ positive displacement refrigerant compression equipment for picking up heat through a closed refrigeration loop external of the space to be conditioned and supplying heat thereto through one coil acting as a system evaporator and releasing that heat to the space being conditioned by a second coil functioning as a condenser within that space, or alternatively, by reversal of refrigerant flow causing heat to be absorbed within the space to be conditioned by employing the coil therein as the system evaporator and discharging the heat external of the space by way of the second coil within the closed loop functioning in that case as the system condenser. Thermal energy may be supplied to the system by means of a third coil from a heat storage media surrounding that coil, which in turn is heated by solar radiation, etc. Further, systems of this type have employed as the usual source of thermal energy an outside coil either within the air external of the space or building being conditioned or within the ground and being connected circuitwise, within the loop and in parallel with the storage coil. The systems include control means for either alternatively or simultaneously connecting both the storage coil and the outside air coil within the closed loop to the compressor and the coil or coils within the space being conditioned, so as to supply when in system heating mode, thermal energy to the space to be conditioned by these sources.
Because of the necessity to reverse refrigerant flow, particularly with respect to the inside coil within the space being conditioned, and the outside coil, either the positive displacement compressor is driven reversely, particularly in the case where the compressor constitutes a helical screw rotary compressor, or reversing valves are employed to switch connections between the discharge and suction sides of the compressor and the respective coils. Such systems have been complicated both in terms of the valving and conduits or lines for connecting the system componentry, and the complexity is magnified where the reversible refrigeration system includes in addition to the outside air coil, storage coil and inside coil, additional coils such as a direct solar energy supply coil, a hot water coil for providing a relatively high temperature water to the building or space to be conditioned, and an additional inside hydronic coil for supplemental heating or cooling of that space or, independently, a section thereof.
Further, the systems tend to be custom designed in that each system is designed independently, depending upon its particular need.
It is, therefore, a primary object of the present invention to provide an improved refrigeration system, particularly of the heat pump type which is of modular form and which completely eliminates the need for a reversing valve and its attendant controls.
It is a further object of the present invention to provide an improved modular refrigeration system which employs a compression module consisting of a multiple cylinder, multiple level reciprocating compressor or a helical screw rotary compressor with porting permitted intermediate pressure return to the compressor and supply therefrom in addition to low pressure suction return and high pressure discharge with the compression modules being interchangeable relative to the remaining componentry of the system.